Question
Question: In the complex [CoCl2(en)2]Br, the co-ordination number and oxidation state of cobalt are :...
In the complex [CoCl2(en)2]Br, the co-ordination number and oxidation state of cobalt are :
A
6 and +3
B
3 and +3
C
4 and +2
D
6 and +1
Answer
6 and +3
Explanation
Solution
Let x be the oxidation state of cobalt in [CoCl2(en)2]+ . So, x + 2(–1) + 0 = +1 or x = + 3.
As there are six s-bonds between cobalt and ligands, it coordination number is 6 (here 'en' is a bidentate ligand).